N.L.’s Atlantic salmon stocks still struggling, says DFO in latest assessment

Canada’s Department of Fisheries and Oceans says Atlantic salmon stocks have declined in most Newfoundland and Labrador rivers in 2022.

In its 2022 assessment of Atlantic salmon stocks in 21 of the province’s rivers, released Tuesday, the DFO said most Newfoundland rivers had “below average yields,” while the Labrador rivers saw some improvements compared to average numbers over the past five years .

Last season, 17 rivers in Newfoundland were monitored. Fifteen of these were graded and two were either not graded or had no reported inventory status.

Nine of the fifteen rivers assessed are in the “critical zone”: less than or equal to 40 percent of what DFO calls “maximum sustainable biomass yield” — the ideal total stock weight that maximizes how much can be fished sustainably — and It is likely to cause serious damage to the stock. A river is in the “caution zone” – the biomass is between 40 and 80 percent of the maximum sustainable yield.

Five rivers were classified as healthy.

Four rivers were surveyed in Labrador last year. One is in the critical zone, one in the caution zone and two are healthy.

“In 2021 we have seen above average yields, strong yields in most monitored rivers across the region. But this year it’s unfortunately gone back, at least for the island part of the province,” DFO salmon stock biologist Nick Kelly said Tuesday.

“We’re seeing quite large declines on the south coast, particularly in the central part of the south coast in the Bay d’Espoir region.”

DFO said the survival and return of young salmon that go to sea remains the “main factor” limiting the population of the stock.

The estimate states that the estimated survival rate in monitored rivers for 2022 ranged from 5.4 to 10.7 percent, with the exception of Conne River and Garnish, where the survival rate ranged from 1.2 to 3.9 percent.

Returns for Conne River were the third lowest since 1986, while Rocky River, Northeast River and Come By Chance River also posted below-average returns.

About 8,000 to 10,000 salmon returned to the river on the Conner River over 30 years ago. Since then, the share has been steadily falling.

“Fewer than 300 fish have returned for the past three years in a row,” Kelly said.

“This spring we’re hoping to deploy a series of acoustic receivers at Bay d’Espoir, which are these foot-long cylinders that can detect markers planted in salmon as they swim by. We trace their migration and survival in Bay d’Espoir.”

At the same time, Kelly said, other DFO scientists will study the possible impact of sea lice on salmon survival.

The DFO listed several factors affecting the return of juvenile salmon, including changing seawater temperatures – 2021 and 2022 were two of the warmest years on record – sea ice, changes in zooplankton and predators.

“When they are at sea, it’s a whole range of complex factors that could affect their survival from year to year. All salmon researchers on both sides of the Atlantic are trying to get a better handle on that,” he told Kelly.

“There may be some impacts from aquaculture activities on wild populations on the south coast.”

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